Investigation of the thermodynamic properties of the binary system vitamin K3/carbon dioxide

Abstract

The binary system of vitamin K3 and CO2 was investigated at temperatures of 40, 60 and 80 ?C up to a pressure of 40 MPa. Solubility was measured by a static-analytic method. Partial molar volumes were determined by a method involving a vibrating tube densimeter. The solubility of vitamin K3 in CO2 is found as a function of pressure and temperature. The highest solubility (31.16?10-4 mol?mol-1) was attained at a pressure of 25.40 MPa at temperature of 40?C. However, at temperature of 60?C and a pressure of 24.02 MPa, the solubility was 18.79?10-4 mol?mol-1. Solubility was lower at a temperature of 80?C and a pressure of 22.06 MPa (6.48?10-4 mol?mol-1). The partial molar volumes are negative and the dissolved vitamin K3 has a minor impact on the density of the solution of K3 in CO2 compared to the density of the pure CO2.